Contrast

Kotlin |Java

@UnstableApi
class Contrast : RgbMatrix

A RgbMatrix to control the contrast of video frames.

Summary

Public constructors
`Contrast(contrast: @FloatRange(from = "-1", to = 1) Float)` Creates a new instance for the given contrast value.

Public functions
`FloatArray<Float>!`	`getMatrix(presentationTimeUs: Long, useHdr: Boolean)` Returns the 4x4 RGB transformation `matrix` to apply to the color values of each pixel in the frame with the given timestamp.
`Boolean`	`isNoOp(inputWidth: Int, inputHeight: Int)` Returns whether a `GlEffect` applies no change at every timestamp.

abstract GlShaderProgram!

toGlShaderProgram(context: Context!, useHdr: Boolean)

Returns a GlShaderProgram that applies the effect.

BaseGlShaderProgram!

toGlShaderProgram(context: Context!, useHdr: Boolean)

Returns a GlShaderProgram that applies the effect.

Contrast(contrast: @FloatRange(from = "-1", to = 1) Float)

Creates a new instance for the given contrast value.

Contrast values range from -1 (all gray pixels) to 1 (maximum difference of colors). 0 means to add no contrast and leaves the frames unchanged.

fun getMatrix(presentationTimeUs: Long, useHdr: Boolean): FloatArray<Float>!

Returns the 4x4 RGB transformation matrix to apply to the color values of each pixel in the frame with the given timestamp.

Parameters
`presentationTimeUs: Long`	The timestamp of the frame to apply the matrix on.
`useHdr: Boolean`	If `true`, colors will be in linear RGB BT.2020. If `false`, colors will be in linear RGB BT.709. Must be consistent with `useHdr` in `toGlShaderProgram`.

Returns
`FloatArray<Float>!`	The `RgbMatrix` to apply to the frame.

fun isNoOp(inputWidth: Int, inputHeight: Int): Boolean

Returns whether a GlEffect applies no change at every timestamp.

This can be used as a hint to skip this instance.

Parameters
`inputWidth: Int`	The input frame width, in pixels.
`inputHeight: Int`	The input frame height, in pixels.